The invention relates to a circuit arrangement of a magnetotherapeutic impulse device, particularly adapted for treatment of inflammatory and degenerative illnesses, such as spondylitis, e.g. Bechterew's disease.
Known magnetotherapeutic devices of this kind are based either on the discharge of a capacitor to the winding of an electromagnet or on a connection of the winding of an electromagnet to a multivibrator circuit, which closes the current circuit of a thyristor coil by a multivibrator at a variable frequency or which closes the current of a coil by a thyristor controlled by an adjusted frequency of the AC line voltage or which closes direct current flowing to the winding of an electromagnet by a mechanical motor driven switch.
A drawback of existing devices involves controlling the power supplied to the electromagnet coils. there is no accurate way to adjust the repeating frequency of the magnetic field, and no way to automatically change the repeating frequency. With existing devices, another drawback is that a maximum of only four coils may be used. Some existing devices synchronize the current to coils with the phase of the supplied voltage and thus provide uniformity of impulses of the magnetic field. The majority of known devices uses mechanical switching, thus in creasing their size and reducing their reliability.